Veterinary Clinical Medicine-I (General and Systemic)

DISORDERS OF PLATELETS IN FARM ANIMALS

Thrombocyte disease

• Includes
  • Thrombocytopenia, a quantitative deficiency in the number of platelets
  • Thrombopathy, any qualitative or functional disorder of platelets, including
  • Thrombasthenia, impaired ADP-induced platelet aggregation and defective clot retraction
• Examples are Thrombocytopenia, Thrombopathy and Thrombasthemia

Thrombocytopenia

• Deficient production cuased by
  • Toxemia
  • Megakaryocyte infections, e.g. by viruses of hog cholera, African swine fever, bovine virus diarrhea
  • Specific poisonings with ptaquiloside, the toxin of stacbytbotrys spp,m furrazolidone, trichloroethylene extracted soybean meal, radiation injury
• Excessive with drawal from circulation-consumption coagulopathy, e.g., as part of disseminated intravascular coagulation.
• Excessive destruction in
  • Maternal isoimmunization causing thrombocytopenic purpura, a rare, fatal disease of neonatal piglets, normal at birth but developing generalized hemorrhages, after sucking colostrum containing antiplatelet antibody. Affected sows should be culled.
  • Idiopathic thrombocytopenia, an immune mediated thrombocytopenia in horses and cattle. Hamorrhages may be confined to a single system. E.g., respiratory or reproductive systems, or the generalized Treatement includes blood transfusion corticosteroids
  • Other immune mediated thrombocytopenias occur, e.g., in drug intoxications, infections or neoplastic diseases. Prothrombin and partial thromboplastin times are normal and there is no disseminated intravascular coagulopathy

Thrombopathy and thrombasthemia

• Non-thrombocytopenic purpuras, e.g:
  • Chediak- Higashi syndrome
  • Inherited Simmental thrompathia